U.S. patent application number 17/327560 was filed with the patent office on 2021-12-02 for toner cartridge and image forming apparatus.
The applicant listed for this patent is CANON KABUSHIKI KAISHA. Invention is credited to Tomofumi Kawamura, Masato Tanabe.
Application Number | 20210373460 17/327560 |
Document ID | / |
Family ID | 1000005651064 |
Filed Date | 2021-12-02 |
United States Patent
Application |
20210373460 |
Kind Code |
A1 |
Kawamura; Tomofumi ; et
al. |
December 2, 2021 |
TONER CARTRIDGE AND IMAGE FORMING APPARATUS
Abstract
A cartridge includes a casing including a toner storage chamber
storing toner and a toner discharge chamber having an outlet, a
conveyance member conveying the toner from the toner storage
chamber to the toner discharge chamber, an action member attached
to the conveyance member and repeating an action of shifting
between an entering state of entering the outlet and a retraction
state of retracting from the outlet, and a pump expanding and
contracting to be shifted between a first state and a second state
in which the internal space is smaller in volume than in the first
state, the pump putting air into the toner discharge chamber by
being shifted from the first state to the second state, thereby
discharging the toner from the toner discharge chamber through the
outlet, and the pump taking in air by being shifted from the second
state to the first state.
Inventors: |
Kawamura; Tomofumi;
(Shizuoka, JP) ; Tanabe; Masato; (Shizuoka,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CANON KABUSHIKI KAISHA |
Tokyo |
|
JP |
|
|
Family ID: |
1000005651064 |
Appl. No.: |
17/327560 |
Filed: |
May 21, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G03G 15/0887
20130101 |
International
Class: |
G03G 15/08 20060101
G03G015/08 |
Foreign Application Data
Date |
Code |
Application Number |
May 28, 2020 |
JP |
2020-093337 |
Claims
1. A cartridge comprising: a casing, the casing including a toner
storage chamber storing toner, and a toner discharge chamber having
an outlet through which the toner is discharged to outside of the
cartridge; a conveyance member configured to rotate and convey the
toner from the toner storage chamber to the toner discharge
chamber; an action member attached to the conveyance member and
configured to rotate with the conveyance member, the action member
being configured to repeat action of shifting between an entering
state in which the action member enters the outlet and a retraction
state in which the action member retracts from the outlet, by
rotation of the conveyance member; and a pump having an internal
space, the pump being configured to expand and contract to be
shifted between a first state and a second state in which the
internal space is smaller in volume than the internal space in the
first state, the pump being configured to put air of the internal
space into the toner discharge chamber by being shifted from the
first state to the second state, thereby discharging the toner from
the toner discharge chamber to outside of the cartridge through the
outlet, the pump being configured to take air into the internal
space by being shifted from the second state to the first
state.
2. The cartridge according to claim 1, wherein the action member is
configured to perform the action of shifting from the retraction
state through the entering state to the retraction state again, at
least once, while the pump is shifted from the second state through
the first state to the second state again.
3. The cartridge according to claim 2, wherein the action member is
a sheet having flexibility, the sheet including an action portion
extending in a direction intersecting a rotation axial direction of
the conveyance member, the action portion repeating the action of
shifting from the retraction state through the entering state to
the retraction state, by the sheet rotating with the conveyance
member.
4. The cartridge according to claim 1, wherein a time period that
the pump is shifted from the second state through the first state
to the second state again is longer than or equal to a time period
that the action member shifts from the retraction state through the
entering state to the retraction state again.
5. The cartridge according to claim 2, wherein the action member is
a sheet having flexibility, the sheet including a first action
portion extending in a direction intersecting a rotation axial
direction of the conveyance member and a second action portion
extending in a direction opposite to the direction in which the
first action portion extends, the first action portion and the
second action portion alternately repeating the action of shifting
from the retraction state through the entering state to the
retraction state again, by the sheet rotating with the conveyance
member.
6. The cartridge according to claim 2, further comprising: a first
gear configured to rotate for expanding and contracting the pump;
and a second gear configured to transmit a driving force to the
conveyance member to rotate the conveyance member, the second gear
being configured to be rotated by a driving force received from the
first gear.
Description
BACKGROUND
Field of the Disclosure
[0001] The present disclosure relates to an image forming apparatus
used to form images on recording media, and toner cartridges used
in the image forming apparatus.
Description of the Related Art
[0002] There is a conventional configuration of an
electrophotographic image forming apparatus which includes a
developer supply container containing toner which is removably
mounted in the main body of the image forming apparatus to supply
the toner (developer) to be consumed in image formation.
[0003] Japanese Patent No. 5623109 discusses a method of supplying
toner from a developer supply container to the main body of an
image forming apparatus, using a pump in the developer supply
container.
SUMMARY
[0004] According to an aspect of the present disclosure, a
cartridge includes a casing, the casing including a toner storage
chamber storing toner, and a toner discharge chamber having an
outlet through which the toner is discharged to outside of the
cartridge, a conveyance member configured to rotate and convey the
toner from the toner storage chamber to the toner discharge
chamber, an action member attached to the conveyance member and
configured to rotate with the conveyance member, the action member
being configured to repeat action of shifting between an entering
state in which the action member enters the outlet and a retraction
state in which the action member retracts from the outlet, by
rotation of the conveyance member, and a pump having an internal
space, the pump being configured to expand and contract to be
shifted between a first state and a second state in which the
internal space is smaller in volume than the internal space in the
first state, the pump being configured to put air of the internal
space into the toner discharge chamber by being shifted from the
first state to the second state, thereby discharging the toner from
the toner discharge chamber to outside of the cartridge through the
outlet, the pump being configured to take air into the internal
space by being shifted from the second state to the first
state.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a schematic view of a configuration of an action
member.
[0006] FIG. 2 is a schematic cross-sectional view of an
electrophotographic image forming apparatus.
[0007] FIG. 3 illustrates a principal section of a process
cartridge.
[0008] FIG. 4 is an overall perspective view of the process
cartridge viewed from front.
[0009] FIGS. 5A and 5B are overall perspective views of the process
cartridge viewed from rear.
[0010] FIG. 6 is an exploded perspective view of a toner
cartridge.
[0011] FIG. 7A is a schematic cross-sectional view of the toner
cartridge viewed from above, and FIG. 7B is a partial
cross-sectional view of the toner cartridge.
[0012] FIG. 8 is a schematic cross-sectional view of the toner
cartridge viewed from the transverse direction.
[0013] FIGS. 9A and 9B are expanded cross-sectional views of a
configuration of a pump of the toner cartridge and a configuration
around the pump.
[0014] FIGS. 10A to 10D are schematic cross-sectional views
illustrating the action of the action member.
[0015] FIG. 11A is a graph illustrating the relationship between
the change in internal pressure of a toner discharge chamber
through expansion/contraction of the pump and time (t), FIG. 11B is
a graph illustrating the relationship between entries and exits of
the action member according to an exemplary embodiment into and
from an outlet and time (t), and FIG. 11C is a graph illustrating
the relationship between entries and exits of an action member
according to a modification example into and from the outlet and
time (t).
DESCRIPTION OF THE EMBODIMENTS
[0016] Some exemplary embodiments will be described below with
reference to the drawings. The dimensions, materials, shapes,
relative positions, and the like of components described in the
exemplary embodiments are changeable as appropriate depending on
the configuration and various conditions of an apparatus to which
the present disclosure is applied, and are not intended to limit
the scope of the disclosure to the following exemplary
embodiments.
<Overall Configuration of Image Forming Apparatus 100>
[0017] An overall configuration of an electrophotographic image
forming apparatus 100 (hereinafter, the image forming apparatus
100) according to an exemplary embodiment will be described with
reference to FIG. 2. FIG. 2 is a schematic view of the image
forming apparatus 100 according to the present exemplary
embodiment. In the present exemplary embodiment, process cartridges
1Y, 1M, 1C, and 1K and toner cartridges (toner supply devices) 13Y,
13M, 13C, and 13K are removably mounted in the main body of the
image forming apparatus 100. In the following description, the
configuration of the image forming apparatus 100 excluding the
process cartridges 1Y, 1M, 1C, and 1K and the toner cartridges 13Y,
13M, 13C, and 13K may be referred to as the main body (apparatus
main body) of the image forming apparatus 100.
[0018] In the present exemplary embodiment, the process cartridges
1Y, 1M, 1C, and 1K serving as four image forming units are
substantially the same in terms of configuration and operation,
except that the colors of images to be formed are different. The
toner cartridges 13Y, 13M, 13C, and 13K are also substantially the
same in terms of configuration and operation, except that the
colors of developers T (hereinafter, the toner) stored therein are
different. In the following description, indexes Y, M, C, and K may
thus be omitted as long as no distinction from each other is made.
Here, the indexes Y, M, C, and K of the reference numerals
represent four colors yellow, magenta, cyan, and black,
respectively.
[0019] As illustrated in FIG. 2, the process cartridges 1 are
horizontally disposed side by side. The process cartridges 1 each
include a cleaning unit 4 and a developing unit 6. The cleaning
unit 4 includes a photosensitive drum 7 serving as an image bearing
member, a charging roller 8 serving as a charging device for
uniformly charging the surface of the photosensitive drum 7, and a
cleaning blade 10 serving as a cleaning member. The developing unit
6 contains a developing roller 11 and toner, and develops an
electrostatic latent image on the photosensitive drum 7. The
cleaning unit 4 and the developing unit 6 are supported to be
swingable relative to each other. The process cartridge 1Y stores
toner of yellow (Y) in the developing unit 6, the process cartridge
1M stores toner of magenta (M), the process cartridge 1C stores
toner of cyan (C), and the process cartridge 1K stores toner of
black (K).
[0020] The process cartridges 1 are removably mounted in the main
body of the image forming apparatus 100, via mounting guides (not
illustrated) in the main body of the image forming apparatus 100
and mounting members such as positioning members (not illustrated).
Further, a scanner unit 12 for forming electrostatic latent images
is under the process cartridges 1. Furthermore, a waste toner
conveyance unit 23 is behind the process cartridges 1 (downstream
in the mounting direction of the process cartridges 1) in the image
forming apparatus 100.
[0021] The toner cartridges 13 are horizontally disposed side by
side, below in the process cartridges 1 in the gravity direction,
in the order corresponding to the colors of toner stored in the
process cartridges 1. The toner cartridges 13 serving as the toner
supply devices may hereinafter be simply referred to as the
cartridge 13. The upward direction opposite the gravity direction
and the gravity direction may hereinafter be simply referred to as
upward and downward, respectively.
[0022] The cartridge 13Y stores toner of yellow (Y), the cartridge
13M stores toner of magenta (M), the cartridge 13C stores toner of
cyan (C), and the cartridge 13K stores toner of black (K). Each of
the cartridges 13 supplies its toner to the process cartridge 1
storing toner of the same color.
[0023] The cartridges 13 perform toner-supply operation when an
insufficient amounts of toner in the process cartridge 1 are
detected by remaining amount detectors (not illustrated) in the
main body of the image forming apparatus 100. The cartridges 13 are
removably mounted in the image forming apparatus 100, via mounting
guides (not illustrated) in the main body of the image forming
apparatus 100 and mounting members such as positioning members (not
illustrated). The process cartridges 1 and the cartridges 13 will
be described in detail below.
[0024] A toner conveyance device 14 for conveying toner from the
corresponding cartridge 13 to the corresponding process cartridge 1
is under the corresponding cartridge 13 in the main body of the
image forming apparatus 100. More specifically, each of the toner
conveyance devices 14 conveys the toner received from the
corresponding cartridge 13 upward, and supplies the toner to the
corresponding developing unit 6. Each toner conveyance device 14
has a passage for conveying toner and a screw in the passage. Toner
is conveyed upward by the rotation of this screw, through the
passage of each toner conveyance device 14.
[0025] An intermediate transfer unit 19 serving as an intermediate
transfer member is disposed over the process cartridges 1. The
intermediate transfer unit 19 is substantially horizontal to the
bottom surface of the image forming apparatus 100, with primary
transfer portions S1 placed downward in the intermediate transfer
unit. An intermediate transfer belt 18 facing the photosensitive
drums 7 is a rotatable endless belt, and is stretched by a
plurality of stretching rollers. On the inner surface of the
intermediate transfer belt 18, primary transfer rollers 20 serving
as primary transfer members are at positions for forming the
primary transfer portions S1 with the photosensitive drums 7 via
the intermediate transfer belt 18 lying therebetween. Further, a
secondary transfer roller 21 serving as a secondary transfer member
is in contact with the intermediate transfer belt 18, and forms a
secondary transfer portion S2 with an opposed roller via the
intermediate transfer belt 18 lying therebetween. Furthermore, a
belt cleaning unit 22 is opposite the process cartridges 1 remote
from the secondary transfer portion S2, in the right-left direction
substantially parallel to the bottom surface of the apparatus main
body and orthogonal to the axial direction of the secondary
transfer roller 21.
[0026] A fixing unit 25 is further above the intermediate transfer
unit 19. The fixing unit 25 includes a heating unit 26 and a
pressure roller 27 in pressure contact with the heating unit 26.
Further, a discharge tray 32 is at the top surface of the apparatus
main body, and a waste toner collection container 24 is between the
discharge tray 32 and the intermediate transfer unit 19.
Furthermore, a sheet feed tray 2 for storing recording media 3 is
at the lowermost in the apparatus main body.
<Image Forming Process>
[0027] Next, an image forming operation in the image forming
apparatus 100 will be described with reference to FIGS. 2 and 3.
FIG. 3 is an enlarged schematic cross-sectional view of a process
cartridge 1 in the present exemplary embodiment.
[0028] As illustrated in FIG. 3, the photosensitive drum 7 is
driven to rotate in the direction indicated by an arrow A at a
predetermined speed in image formation. The intermediate transfer
belt 18 is driven to rotate in the direction indicated by an arrow
B in FIG. 2 (in the forward direction with respect to the rotation
of the photosensitive drum 7).
[0029] First, the surface of the photosensitive drum 7 is uniformly
charged by the charging roller 8 as the photosensitive drum 7
rotates. Next, the charged surface of the photosensitive drum 7 is
scan-exposed by laser beams emitted from the scanner unit 12,
forming an electrostatic latent image based on image information on
the photosensitive drum 7. The electrostatic latent image on the
photosensitive drum 7 is developed in a toner image by the
developing unit 6. In this process, the developing unit 6 is urged
toward the photosensitive drum 7 by a development pressure unit
(not illustrated) in the apparatus main body. Subsequently, the
toner image on the photosensitive drum 7 is primarily transferred
from the photosensitive drum 7 onto the intermediate transfer belt
18 by the corresponding primary transfer roller 20 with a
predetermined voltage applied thereto, at the primary transfer
portion S1.
[0030] Here, in forming a full color image, the above-described
processes are sequentially performed at the primary transfer
portions S1Y, S1M, S1C, and S1K, so that the toner images of the
respective colors are superimposed on the intermediate transfer
belt 18.
[0031] Each of the recording media 3 stored in the sheet feed tray
2 is fed at a predetermined control timing, and conveyed to the
secondary transfer portion S2 in synchronization with the movement
of the intermediate transfer belt 18. Subsequently, at the
secondary transfer portion S2, a predetermined voltage is applied
to the secondary transfer roller 21 in contact with the recording
medium 3 on the intermediate transfer belt 18, so that the toner
images of the four colors on the intermediate transfer belt 18 are
collectively transferred onto the recording medium 3.
[0032] Afterward, the recording medium 3 with the toner images
thereon is conveyed to the fixing unit 25. The recording medium 3
is heated and pressed in the fixing unit 25, so that the toner
images are fixed to the recording medium 3. The recording medium 3
after the fixing is then conveyed onto the discharge tray 32, which
completes the image forming operation.
[0033] The primary-transfer residual toner (waste toner) remaining
on the photosensitive drum 7 after the primary transfer to the
intermediate transfer belt 18 is removed from the surface of the
photosensitive drum 7 with the cleaning blade 10. Further, the
secondary-transfer residual toner (waste toner) remaining on the
intermediate transfer belt 18 after the secondary transfer to the
recording medium 3 is removed from the surface of the intermediate
transfer belt 18 with the belt cleaning unit 22. The waste toner
removed with the cleaning blade 10 and the belt cleaning unit 22 is
conveyed by the waste toner conveyance unit 23 in the apparatus
main body, and stored in the waste toner collection container 24.
The image forming apparatus 100 can form a single color image or
multicolor image, using one or a few (not all) of the image forming
units.
<Process Cartridge>
[0034] Next, an overall configuration of a process cartridge 1
mounted in the main body of the image forming apparatus 100
according to the present exemplary embodiment will be described
with reference to FIGS. 3, 4, 5A, and 5B. FIG. 4 is a schematic
perspective view of the configuration of the process cartridge 1
viewed from the upstream side in the mounting direction of the
process cartridge 1. FIG. 5A is a schematic perspective view of the
configuration of the process cartridge 1 viewed from the downstream
side in the mounting direction of the process cartridge 1 and in
view of the cleaning unit 4. FIG. 5B is a schematic perspective
view of the configuration of the process cartridge 1 viewed from
the downstream side in the mounting direction of the process
cartridges 1 and in view of the developing unit 6.
[0035] As illustrated in FIGS. 3 and 4, the process cartridge 1 is
composed of the cleaning unit 4 and the developing unit 6. The
cleaning unit 4 and the developing unit 6 are combined to be
swingable about a rotation support pin 30.
[0036] As illustrated in FIG. 3, the cleaning unit 4 includes a
cleaning frame 5 supporting various members in the cleaning unit 4.
The cleaning unit 4 further includes a waste toner screw 15
extending in the direction parallel to the rotation axial direction
of the photosensitive drum 7, in addition to the photosensitive
drum 7, the charging roller 8, and the cleaning blade 10. On the
cleaning frame 5, a cleaning bearing 33 is at each of both ends of
the cleaning unit 4 in the longitudinal direction thereof. The
cleaning bearing 33 rotatably supports the photosensitive drum 7,
and includes a cleaning gear train 31 for transmitting a driving
force from the photosensitive drum 7 to the waste toner screw
15.
[0037] The charging roller 8 in the cleaning unit 4 is urged in the
direction indicated by an arrow C toward the photosensitive drum 7,
by a charging roller pressure spring 36 at each of both ends of the
charging roller 8 in the axial direction thereof. The charging
roller 8 rotates following the photosensitive drum 7, and the
driven rotation of the photosensitive drum 7 in the direction
indicated by the arrow A in image formation causes the charging
roller 8 to rotate in the direction indicated by an arrow D (in the
forward direction with respect to the rotation of the
photosensitive drum 7).
[0038] The cleaning blade 10 in the cleaning unit 4 is composed of
an action member 10a for removing residual toner (waste toner)
remaining on the surface of the photosensitive drum 7 after the
primary transfer, and a support member 10b for supporting the
action member 10a. The waste toner removed from the surface of the
photosensitive drum 7 with the cleaning blade 10 is stored in a
waste toner storage chamber 9 formed by the cleaning blade 10 and
the cleaning frame 5. The waste toner stored in the waste toner
storage chamber 9 is conveyed toward the back of the image forming
apparatus 100 (toward the downstream side in the mounting direction
of the process cartridge 1) by the waste toner screw 15 in the
waste toner storage chamber 9. The conveyed waste toner is
discharged out of a waste toner discharge port 35 illustrated in
FIG. 5A, and is delivered to the waste toner conveyance unit 23 in
the main body of the image forming apparatus 100.
[0039] The developing unit 6 includes a developing frame 16
supporting various members in the developing unit 6. The developing
frame 16 is divided into a developing chamber 16a including the
developing roller 11 and a supply roller 17, and a toner storage
chamber 16b storing toner and including a stirring member 29.
[0040] The developing roller 11, the supply roller 17, and a
developing blade 28 are in the developing chamber 16a. The
developing roller 11 bears toner, and rotates in the direction
indicated by an arrow E to supply toner to the photosensitive drum
7 in contact with the photosensitive drum 7 in image formation.
Further, the developing roller 11 is rotatably supported on the
developing frame 16 by a development bearing unit 34, at each of
both ends in the longitudinal direction (the rotation axial
direction) thereof. The supply roller 17 is in contact with the
developing roller 11, and rotatably supported on the developing
frame 16 by the development bearing unit 34, and rotates in the
direction indicated by an arrow F in image formation. Further, the
developing blade 28 serving as a layer-thickness regulating member
for regulating the thickness of a toner layer formed on the
developing roller 11 is in contact with the surface of the
developing roller 11.
[0041] The stirring member 29 for stirring toner (toner T) and
conveying toner to the supply roller 17 through a developing
chamber communication port 16c is in the toner storage chamber 16b.
The stirring member 29 includes a rotating shaft 29a parallel with
the rotation axial direction of the developing roller 11, and a
stirring sheet 29b serving as a conveyance member that is a
flexible sheet. One end of the stirring sheet 29b is attached to
the rotating shaft 29a, and the other end of the stirring sheet 29b
is a free end. The rotation of the rotating shaft 29a in the
direction indicated by an arrow G causes toner to be stirred by the
stirring sheet 29b.
[0042] The developing unit 6 includes the developing chamber
communication port 16c through which the developing chamber 16a
communicates with the toner storage chamber 16b. In the present
exemplary embodiment, the developing chamber 16a is located above
the toner storage chamber 16b, in the orientation when the
developing unit 6 is normally used (the orientation when in use).
Toner in the toner storage chamber 16b is scooped by the stirring
member 29 and scooped toner is supplied to the developing chamber
16a through the developing chamber communication port 16c.
[0043] Further, as illustrated in FIG. 5B, a toner receiving inlet
40 is located at one end of the developing unit 6, downstream in
the mounting direction of the process cartridge 1. An inlet seal
member 45 and a toner receiving inlet shutter 41 movable in the
front-back direction are at the toner receiving inlet 40. With no
process cartridge 1 mounted in the apparatus main body, the toner
receiving inlet 40 is closed with the toner receiving inlet shutter
41. The toner receiving inlet shutter 41 opens and closes
interlocking with the mounting/removing operation of the process
cartridge 1. As the process cartridge 1 is mounted, the apparatus
main body forces the toner receiving inlet shutter 41 open.
[0044] As illustrated in FIG. 3, a receiving conveyance passage 42
communicates with the toner receiving inlet 40, and includes a
receiving conveyance screw 43. Further, a storage chamber
communication port 44 for supplying toner to the toner storage
chamber 16b is near the center of the developing unit 6 in the
longitudinal direction thereof, and is connected with the receiving
conveyance passage 42 and the toner storage chamber 16b. The
receiving conveyance screw 43 extends in the direction parallel to
the rotation axial direction of the developing roller 11 and the
supply roller 17, and conveys toner received from the toner
receiving inlet 40 to the toner storage chamber 16b through the
storage chamber communication port 44.
<Toner Cartridge>
[0045] Next, an overall configuration of a cartridge 13 (the toner
supply device) to be mounted in the image forming apparatus 100
according to the present exemplary embodiment will be described
with reference to FIGS. 6, 7A, 7B, 8, 9A, and 9B. In the present
exemplary embodiment, the cartridge 13K storing toner of black (K)
has a larger toner capacity than those of the other three color
cartridges 13Y, 13M, and 13C. Except for the capacity, the
configurations of the four cartridges 13 are substantially the
same. The following is a description with reference to the drawings
of configurations of the cartridges 13Y, 13M, and 13C, which store
color toners yellow (Y), magenta (M), and cyan (C), respectively.
The indexes Y, M, and C of the reference numerals will be omitted
in the description.
[0046] FIG. 6 is a schematic perspective view of a partially
exploded configuration of the cartridge 13 according to the present
exemplary embodiment. FIG. 7A is a schematic cross-sectional view
of the cartridge 13 viewed from above, and FIG. 7B is a
cross-sectional view taken along a line A1-A1 in FIG. 7A. FIG. 8 is
a schematic cross-sectional view of the configuration of the
cartridge 13 taken along a line A2-A2 in FIG. 7A. FIG. 9A is a
schematic view of a pump 58 being expanded in the
expansion/contraction direction thereof in the present exemplary
embodiment, and FIG. 9B is a schematic view of the pump 58 being
contracted in the expansion/contraction direction in the present
exemplary embodiment.
[0047] In the following description, on the assumption that the
cartridge 13 is in a normal orientation, in which the cartridge 13
is mounted in the apparatus main body, directions indicated by
arrows X1, X2, Y1, Y2, Z1, and Z2 using an X-axis, a Y-axis, and a
Z-axis are defined as follows. Here, the X-axis, the Y-axis, and
the Z-axis are orthogonal to each other.
[0048] The upward direction opposite the gravity direction and the
downward direction in the gravity direction are indicated by the
Y-axis. The upward direction is indicated by the arrow Y1, and the
downward direction is indicated by the arrow Y2. The surface at the
end of the cartridge 13 in the Y1 direction will be referred to as
the upper surface (the top surface), and the surface at the end in
the Y2 direction will be referred to as the bottom surface. The
upper surface of the cartridge 13 faces upward (in the Y1
direction), and the bottom surface faces downward (in the Y2
direction).
[0049] The frontward and backward directions are indicated by the
Z-axis. In the mounting direction in mounting the cartridge 13 in
the apparatus main body, the upstream direction is indicated by the
arrow Z1, and the downstream direction is indicated by the arrow
Z2. The Z1 direction is the frontward direction, and the Z2
direction is the backward direction. In other words, the surface at
the end of the cartridge 13 in the Z1 direction will be referred to
as the front surface, and the surface at the end in the Z2
direction will be referred to as the back surface. The front
surface of the cartridge 13 faces frontward (in the Z1 direction),
and the back surface thereof faces backward (in the Z2 direction).
The extent from the front surface to the back surface (the extent
in the Z-axis direction) is in the longitudinal direction of the
cartridge 13.
[0050] Further, the leftward and rightward directions are dedicated
by the X-axis. Viewed in the direction of mounting the cartridge 13
in the apparatus main body, the leftward direction is indicated by
the arrow X1, and the rightward direction is indicated by the arrow
X2. The surface at the end of the cartridge 13 in the X1 direction
will be referred to as the left side surface (the left surface),
and the surface at the end in the X2 direction will be referred to
as the right side surface (the right surface). The left side
surface of the cartridge 13 faces leftward (in the X1 direction),
and the right side surface faces rightward (in the X2 direction).
The direction from the left side surface to the right side surface
(i.e., the extent along the X-axis) is in the transverse direction
of the cartridge 13.
[0051] In the present exemplary embodiment, the distance between
the front surface and the back surface of the cartridge 13 is
longer than the distance between the right side surface and the
left side surface, and longer than the distance between the top
surface and the bottom surface. The distance between the right side
surface and the left side surface is shorter than the distance
between the top surface and the bottom surface. However, the
present exemplary embodiment is not limited to such a
configuration. For example, the distance between the right side
surface and the left side surface or the top surface and the bottom
surface of the cartridge 13 may be the longest.
[0052] Toner to be supplied to the corresponding developing unit 6
by the cartridge 13 is supplied to the corresponding process
cartridge 1 by the corresponding toner conveyance device 14 as
described above. In short, the cartridge 13 stores the toner to be
supplied to the process cartridge 1.
[0053] As illustrated in FIG. 6, the cartridge 13 of the present
exemplary embodiment includes a supply frame (a casing or frame)
50. The supply frame 50 includes a container 50a and a cover 50b,
and the cover 50b is added to the container 50a. The container 50a
and the cover 50b form an internal space 51 in the supply frame 50.
The cover 50b is at the end of the cartridge 13 in the Y1
direction, and forms the upper surface of the cartridge 13 (the
upper surface of the supply frame 50).
[0054] The supply frame 50 includes a partition member (a
partition) 55 in the internal space 51, and the internal space 51
is further partitioned into a plurality of areas by the partition
member 55. In other words, as illustrated in FIG. 8, the partition
member 55 partitions the internal space 51 into a plurality of
rooms (spaces) including a toner storage chamber 49, a
communication passage 48, and a toner discharge chamber 57. The
partition member 55 can be regarded as a part of the supply frame
50 or be actually formed integrally with the supply frame 50.
[0055] Further, a gear train composed of a driving force input gear
59, a cam gear 60 (a first gear), and a screw gear 64 (a second
gear), and the pump 58 are attached near the end (the rear end, or
the back surface) of the supply frame 50 in the Z2 direction. To
cover the gear train and the pump 58, a side cover 62 is attached
outside these members. In particular, the movement of the cam gear
60 is restricted by the side cover 62 and the supply frame 50 in
the Z1 and Z2 directions.
[0056] As illustrated in FIGS. 6 to 8, a stirring member 53 and a
screw 54 (a conveyance member) are in the internal space 51 of the
supply frame 50. The screw 54 extends from the upstream (the Z1
direction) to the downstream (the Z2 direction) in the mounting
direction of the cartridge 13. Further, as illustrated in FIG. 8,
the screw 54 has a part extending in the Z1 direction and in the Z2
direction covered with the partition member 55. The part of the
screw 54 covered with the partition member 55 forms a tunnel-shaped
space as the communication passage 48 in the partition member
55.
[0057] Each of the rooms (spaces) formed in the internal space 51
of the supply frame 50 will be described in detail.
[Toner Storage Chamber]
[0058] As illustrated in FIGS. 7A and 7B, the toner storage chamber
(a developer storage chamber) 49 has a space for storing toner
(developer), and the stirring member 53 for stirring the toner is
in the toner storage chamber 49. The stirring member 53 extends in
the direction parallel to the longitudinal direction of the
cartridge 13, and is rotatably supported by the supply frame
50.
[0059] The stirring member 53 includes a rotating shaft 53a and a
supply stirring sheet 53b as a flexible sheet member. The rotating
shaft 53a extends in the direction where the stirring member 53
extends (the longitudinal direction of the cartridge 13). Further,
one end of the supply stirring sheet 53b is attached to the
rotating shaft 53a. The other end of the supply stirring sheet 53b
is a free end, and the rotation of the rotating shaft 53a causes
the supply stirring sheet 53b to rotate in the direction indicated
by an arrow H illustrated in FIG. 7B. The rotation of the supply
stirring sheet 53b causes the toner stored in the toner storage
chamber 49 to be stirred and conveyed to the screw 54 serving as a
supply conveyance screw to be described below.
[Communication Passage]
[0060] The communication passage 48 is a space in which the toner
storage chamber 49 communicates with the toner discharge chamber 57
to be described below, and the toner travels in this space. The
communication passage 48 is formed by the partition member 55 and
the supply frame 50. As described above, the part of the screw 54
is in the communication passage 48. To be more specific, in the
internal space 51 of the supply frame 50 as illustrated in FIG. 8,
the partition member 55 is not in an area of the screw 54 in the Z1
direction but in an area in the Z2 direction. The space partitioned
by the partition member 55 in the Z2 direction is the communication
passage 48, and the space of the screw 54 in the Z1 direction
directly is connected with the toner storage chamber 49. In other
words, the screw 54 is in both the space directly connected with
the toner storage chamber 49 and the communication passage 48.
[0061] The screw 54 is a member movable relative to the supply
frame 50, and more specifically, the screw 54 is rotatably
supported by the supply frame 50. The screw 54 rotates to convey
toner in the toner storage chamber 49 in the rotation axial
direction of the screw 54 from the part exposed in the toner
storage chamber 49 extending in the Z1 direction toward the
communication passage 48 extending in the Z2 direction.
[0062] As described above, the communication passage 48 is formed
in a tunnel shape by the partition member 55 and the supply frame
50, and extends in the direction of the toner conveyance by the
screw 54e. Further, the screw 54 is partially covered to be in the
communication passage 48. The tunnel shape of the communication
passage 48 is formed to accommodate to the external form of the
screw 54.
[0063] The communication passage 48 plays a role of regulating the
amount of toner conveyed by the screw 54 to convey a predetermined
amount of toner. To be more specific, some toner conveyed by the
screw 54 toward the communication passage 48 enters the
communication passage 48 and moves to the toner discharge chamber
57, but the other toner does not enter the communication passage 48
and remains in the toner storage chamber 49. The amount of the
toner entering the communication passage 48 is adjusted in a ratio
set as appropriate between the size of the opening of the tunnel
formed by the communication passage 48 and the size of the screw
54. Thus, the screw 54 extending in the communication passage 48
allows a predetermined amount of toner to be supplied from the
toner storage chamber 49 into the toner discharge chamber 57.
[Toner Discharge Chamber]
[0064] As illustrated in FIGS. 8, 9A, and 9B, the toner discharge
chamber 57 is a space formed by the partition member 55 and the
supply frame 50, and is disposed downstream from the communication
passage 48 in the conveyance direction (the Z2 direction) in which
the screw 54 conveys toner.
[0065] Near the toner discharge chamber 57, which is near the back
surface (the end in the Z2 direction) of the supply frame 50, is
disposed the screw gear 64 to receive a rotary force for rotating
the screw 54. Further, the toner discharge chamber 57 has an outlet
52 for discharging toner from the internal space 51 of the supply
frame 50 to the outside. The outlet 52 is formed in the bottom
surface of the cartridge 13 (the bottom surface of the supply frame
50), and toner is discharged downward out of the outlet 52.
Further, as illustrated in FIG. 2, below the cartridge 13 lies the
corresponding toner conveyance device 14 and the toner discharged
from the outlet 52 is put in the toner conveyance device 14 and
then conveyed to the corresponding process cartridge 1 by the toner
conveyance device 14. The outlet 52 is disposed downstream of the
cartridge 13 in the conveyance direction of the screw 54. In other
words, the distance between the outlet 52 and the back surface (the
end in the Z2 direction) of the cartridge 13 is shorter than the
distance between the outlet 52 and the front surface (the end in
the Z1 direction) of the cartridge 13.
[0066] Furthermore, the pump 58 is near the back surface (the end
in the Z2 direction) of the cartridge 13. The pump 58 includes a
bellows portion (a movable portion) 58a to expand and contract to
change the volume of the internal space, and the pump 58
communicates with the inside of the toner discharge chamber 57. The
cam gear 60 rotates to expand or contract the bellows portion 58a,
changing the internal volume of the internal space of the bellows
portion 58a. In other words, the pump 58 is configured to expand
and contract in the range between a first state of a relatively
larger volume of the internal space of the bellows portion 58a and
a second state of a relatively smaller volume of the internal space
of the bellows portion 58a than that in the first state. The first
state and the second state are a maximized capacity and a minimized
capacity of the bellows portion 58a, respectively, formed by the
rotation of the cam gear 60.
[0067] As illustrated in FIG. 6, the cam gear 60 engages the
driving force input gear 59 and the screw gear 64, and configured
to be rotated by a driving force received from the driving force
input gear 59 and thereby to transmit the rotary force to the screw
gear 64.
[0068] The varying internal pressure (internal atmospheric
pressure) of the toner discharge chamber 57 with the
expansion/contraction of the pump 58 makes a difference between an
atmospheric pressure outside the cartridge 13 and the pressure
inside the toner discharge chamber 57. The outlet 52 takes in and
releases air due to pressure differences, and the flows of the air
contributes to the discharge of toner out of the outlet 52 toward
the toner conveyance device 14.
[0069] To be more specific, as the capacity of the pump 58
increases through expansion of the pump 58 as illustrated in FIG.
9A, the atmospheric pressure in the pump 58 and the toner discharge
chamber 57 decreases, whereby air is taken into the toner discharge
chamber 57 through the outlet 52. In other words, a shift from the
second state to the first state of the bellows portion 58a causes
air to be taken into the toner discharge chamber 57 through the
outlet 52. On the other hand, as the capacity decreases through
contraction of the pump 58 as illustrated in FIG. 9B, the
atmospheric pressure in the pump 58 and the toner discharge chamber
57 increases, whereby toner is discharged with air from the inside
of the toner discharge chamber 57 to the outside through the outlet
52. In other words, a shift from the first state to the second
state of the bellows portion 58a causes air to be sent from the
bellows portion 58a into the toner discharge chamber 57, whereby
toner is discharged from the toner discharge chamber 57 through the
outlet 52. These processes are repeated so that toner is
intermittently discharged from the inside of the cartridge 13 to
the outside through the outlet 52 in the configuration of the
present exemplary embodiment.
[Configuration of Action Member]
[0070] Next, a configuration of an action member 70 according to
the present exemplary embodiment will be described with reference
to FIG. 1. FIG. 1 is an enlarged view of the end of the screw 54 in
the Z2 direction.
[0071] As illustrated in FIGS. 1 and 9A, the action member 70 is
mounted at the position of the screw 54 above the outlet 52. In the
present exemplary embodiment, a sheet-like elastic member, more
specifically, a resin sheet (a polycarbonate sheet) with a
thickness of 100 .mu.m, is used for the action member 70. The
action member 70 is fixed to the screw 54 by thermal fixing by
melting the upper portion of a boss 54a flat on the action member
70. As illustrated in FIG. 1, the action member 70 includes a first
blade 70a (a first action portion) and a second blade 70b (a second
action portion) each protruding in a direction orthogonal to the
rotation axial direction of the screw 54. These blades of the
action member 70 repeat entries into and exits (retract) from the
outlet 52, as the screw 54 rotates. The actions of an entry into
and an exit from the outlet 52 of the action member 70 allows the
toner near the outlet 52 to get loosened. As the screw 54 rotates,
the action member 70 repeatedly shifts from an entering state where
the action member 70 enters the outlet 52 to a retraction state
where the action member 70 retracts from the outlet 52, and vice
versa.
[Action of Action Member]
[0072] Next, the action of the action member 70 will be described
more in detail with reference to FIGS. 9A, 9B, and 10A to 10D.
FIGS. 10A to 10D are schematic cross-sectional views illustrating
the action of the action member 70, each taken along a line A3-A3
in FIG. 7A. As illustrated in FIGS. 10A to 10D, the screw 54
rotates in the direction indicated by an arrow R1, and the action
member 70 rotates with the screw 54 while deforming inside the
toner discharge chamber 57.
[0073] FIG. 10A illustrates a driven state of the screw 54 at a
moment, a state where the attachment surface of the action member
70 is at the position opposite the rotating shaft of the screw 54
remote from the outlet 52 and is horizontal to the opening surface
of the outlet 52. In this state, the first blade 70a and the second
blade 70b are deformed along the partition member 55 and the supply
frame 50 due to the flexibility of the action member 70. As
described above here, a certain amount of toner is constantly sent
into the toner discharge chamber 57 by the screw 54 through the
communication passage 48, and thus the space near the outlet 52 is
filled with a constant amount of toner.
[0074] When the screw 54 rotates after the state in FIG. 10A in the
R1 direction, the deformation of the first blade 70a arriving at
the outlet 52 is relieved and the first blade 70a enters the outlet
52 as illustrated in FIG. 10B. As the first blade 70a thus enters
the outlet 52, the toner in and near the outlet 52 gets loose,
increasing the flowability of the toner. The action member 70 as
flexible sheet material allows the blade of the action member 70 to
enter the outlet 52, having an effect of loosening toner. In
addition, in the configuration of the present exemplary embodiment,
the first blade 70a enters the outlet 52 but does not cover the
outlet 52 completely as illustrated in FIG. 10B, and thus the
discharge of the toner is not disrupted even if the pump 58
contracts to perform the discharge operation.
[0075] When the screw 54 rotates after the state in FIG. 10B
further in the R1 direction, the first blade 70a exits from the
outlet 52, as illustrated in FIG. 10C. In this state, the first
blade 70a and the second blade 70b are deformed along the partition
member 55 and the supply frame 50, as with the state in FIG. 10A.
In the state in FIG. 10C, the attachment surface of the action
member 70 is horizontal to the opening surface of the outlet
52.
[0076] When the screw 54 rotates after the state in FIG. 10C
further in the R1 direction, the second blade 70b opposite the
first blade 70a arrives at the outlet 52 and the deformation of the
second blade 70b is relieved in the outlet 52, as illustrated in
FIG. 10D. The second blade 70b thereby enters the outlet 52. In
this state, as the second blade 70b enters the outlet 52, the toner
in and near the outlet 52 gets loosened, increasing the
flowability, bringing the toner into a state suitable for the
discharge of the toner, as with the state described with reference
to FIG. 10B.
[0077] As described above, the action member 70 shifts from the
state in FIG. 10A to the state in FIG. 10D to cause the two blades
to alternately repeat an entry into and an exit from the outlet 52
while the screw 54 rotates once, allowing the toner in and near the
outlet 52 to get loosened. In short, the two blades alternately
repeat the action of shifting from the retraction state via the
entering state to the retraction state again.
[Cyclic Relationship Between Expansion/Contraction of Pump and
Rotation of Action Member]
[0078] Next, the cyclic relationship between the
expansion/contraction action of the pump 58 and the rotation of the
action member 70 in the present exemplary embodiment will be
described with reference to FIGS. 11A to 11C. FIG. 11A is a graph
illustrating the relationship between the change in the internal
pressure of the toner discharge chamber 57 and time (t) through the
expansion/contraction action of the pump 58 in operation. FIG. 11B
is a graph illustrating the relationship between entries and exits
of the action member 70 in the present exemplary embodiment into
and from the outlet 52 and time (t). FIG. 11C is a graph
illustrating the relationship between entries and exits into and
from the outlet 52 of the action member and time (t) with an action
member having the first blade, as a modification example of the
present exemplary embodiment.
[0079] As illustrated in FIG. 11A, the pump 58 moves to expand and
contract as the cam gear 60 is rotated by the driving force
received from the driving force input gear 59, fluctuating the
internal pressure of the toner discharge chamber 57 in a cycle (Tp)
of the expansion/contraction of the pump 58. In the configuration
of the present exemplary embodiment, the rotation speed of the cam
gear 60 is set to 79 (rpm), and the cycle Tp of the pump is set to
0.38 (sec). In FIG. 11A, an area P1 is an area where the internal
pressure of the toner discharge chamber 57 is higher than the
external pressure, and an area P2 is an area where the internal
pressure of the toner discharge chamber 57 is lower than the
external pressure. The internal pressure of the toner discharge
chamber 57 fluctuates as the pump 58 expands and contracts as
illustrated in FIG. 11A. As described above, toner is discharged
from the outlet 52 as the pump 58 contracts, specifically, in the
area P1.
[0080] FIG. 11B illustrates the relationship between entries and
exits of the first blade 70a and the second blade 70b of the action
member 70 into and from the outlet 52 in expansion/contraction
cycles of the pump 58, described in the present exemplary
embodiment. In the present exemplary embodiment, the screw gear 64
is rotated by a driving force received from the cam gear 60, which
causes the screw 54 to rotate. In other words, the cam gear 60 for
driving the pump 58 and the screw gear 64 for driving the screw 54
engage, allowing the blades of the action member 70 to enter and
exit the outlet 52 in harmony with expansion/contraction cycles of
the pump 58. Such a configuration makes it easy for the
expansion/contraction cycle of the pump 58 and the action of the
action member 70 to be cyclic.
[0081] In the present exemplary embodiment, the rotation speed of
the screw 54 is set to 174 (rpm), and the cycles of the two blades
of the action member 70 are set to 0.11 (sec) as a time period Ts1
and 0.24 (sec) as a time period Ts2. The time period Ts1 in FIG.
11B here is a time interval from the moment that the first blade
70a enters the outlet 52 to the moment that the second blade 70b
enters the outlet 52. The time period Ts2 is a time interval from
the moment that the second blade 70b enters the outlet 52 to the
moment that the first blade 70a enters the outlet 52.
[0082] A time t1 in FIG. 11A is a timing that the pump 58 begins to
contract to start discharging the toner, and a time t2 is a timing
that the pump 58 begins to contract again to start discharging the
toner after the pump 58 has contracted and expanded once. In the
configuration of the present exemplary embodiment, the toner near
the outlet 52 gets loosened twice with the first blade 70a and the
second blade 70b during the time period from the time t1 to the
time t2 (one cycle of the expansion/contraction of the pump 58), as
illustrated in FIGS. 11A and 11B. This provides a stable discharge
operation of the toner through the action of the action member 70
with the expansion/contraction of the pump 58. The time period from
the time t1 to the time t2 (one cycle of the expansion/contraction
of the pump 58), in other words, is a time period from the moment
that the pump 58 discharges the toner from the outlet 52, through
one intake of air, to the moment that the toner is next discharged
from the outlet 52.
[0083] To discharge the toner stably through the action of the
action member 70 with the expansion/contraction of the pump 58, it
is suitable to perform the entry and exit action of the blade of
the action member 70 into and from the outlet 52 at least once,
during the time period from the time t1 to the time t2. Namely,
with the first and second blades provided as in the present
exemplary embodiment, it is suitable that the cycle Tp of the pump
58 is longer than or equal to the time period Ts1 and longer than
or equal to the time period Ts2. In other words, it is suitable
that the action member 70 goes through the action from the exit
(retraction) state through the entering state then to the exit
state again, at least once, during the time period that the pump 58
is shifted from the second state (FIG. 9A), via the first state
(FIG. 9B), to the second state again (FIG. 9A).
[0084] To loosen the toner near the outlet 52 at least once during
the time period from the time t1 to the time t2, the action member
may have one blade, one of the two blades illustrated in FIG. 1, as
a modification example, instead of having the two blades in the
present exemplary embodiment. In this case, the cycle of entry and
exit of the action member into and from the outlet 52 is as
illustrated in FIG. 11C. A time period Ts3 in FIG. 11C here is a
time interval from the moment that the blade enters the outlet 52,
through one rotation of the screw 54 after the blade exits from the
outlet 52, to the moment that the blade enters the outlet 52 again.
To discharge the toner stably through the action of the action
member 70 with the expansion/contraction of the pump 58 in the
configuration, it is suitable that the cycle Tp of the pump is
longer than or equal to the time period Ts3.
[0085] In the configuration of the present exemplary embodiment as
described above, in the cartridge 13 to supply toner using the pump
58, the action member 70, attached to the screw 54, is operated
with the expansion/contraction of the pump 58. This allows toner
near the outlet 52 to be loosened with one or more blades of the
action member 70 in harmony with the expansion/contraction cycle of
the pump 58, providing a stable discharge of toner from the outlet
52.
[0086] In the present exemplary embodiment, the configuration where
the cam gear 60 for driving the pump 58 and the screw gear 64 for
driving the screw 54 engage has been described, but the present
exemplary embodiment is not limited thereto. A different driving
unit may transmit a driving force to the screw gear 64 instead of
the cam gear 60 as long as the toner near the outlet 52 is loosened
at least once during the time period from the time t1 to the time
t2 (one cycle of the expansion/contraction of the pump 58).
[0087] The action member 70 is not limited to the resin sheet
described in the present exemplary embodiment, and another material
having a similar function is usable in place of the resin, and the
thickness thereof is appropriately adjustable as long as the action
member 70 enters and exits the outlet 52 with the rotation of the
screw 54. Moreover, the attachment of the action member 70 to the
screw 54 is not limited to the thermal fixing described in the
present exemplary embodiment, and a fixing method having a function
equivalent to the thermal fixing is usable as appropriate.
[0088] While the present disclosure has been described with
reference to exemplary embodiments, it is to be understood that the
disclosure is not limited to the disclosed exemplary embodiments.
The scope of the following claims is to be accorded the broadest
interpretation so as to encompass all such modifications and
equivalent structures and functions.
[0089] This application claims the benefit of priority from
Japanese Patent Application No. 2020-093337, filed May 28, 2020,
which is hereby incorporated by reference herein in its
entirety.
* * * * *